How to set a custom consumer task executor for Spring Kafka, when using auto-configuration?

Question

In lines 226-230 of org.springframework.kafka.listener.KafkaMessageListenerContainer, Spring Kafka assigns a default SimpleAsyncTaskExecutor as the listener container's consumer task executor:

    if (containerProperties.getConsumerTaskExecutor() == null) {
        SimpleAsyncTaskExecutor consumerExecutor = new SimpleAsyncTaskExecutor(
                (getBeanName() == null ? "" : getBeanName()) + "-C-");
        containerProperties.setConsumerTaskExecutor(consumerExecutor);
    }

In the docs, it is pointed out that it is possible to use a custom executor instead of SimpleAsyncTaskExecutor:

If you don’t provide a consumer executor, a SimpleAsyncTaskExecutor is used; this executor creates threads with names <beanName>-C-1 (consumer thread). For the ConcurrentMessageListenerContainer, the <beanName> part of the thread name becomes <beanName>-m, where m represents the consumer instance. n increments each time the container is started. So, with a bean name of container, threads in this container will be named container-0-C-1, container-1-C-1 etc., after the container is started the first time; container-0-C-2, container-1-C-2 etc., after a stop/start.

However I can't find a way to customize the executor when Spring Boot's auto-configuration is enabled for Kafka (i.e. KafkaAutoConfiguration).

In short, what is the correct way to set (ContainerProperties#consumerTaskExecutor)?

Answer 1

是的，你不能通过配置属性来做到这一点，因为它不是那么简单的属性，但你可以覆盖bean：

@Bean
@ConditionalOnMissingBean
public ConcurrentKafkaListenerContainerFactoryConfigurer kafkaListenerContainerFactoryConfigurer() {
    ConcurrentKafkaListenerContainerFactoryConfigurer configurer = new ConcurrentKafkaListenerContainerFactoryConfigurer();
    configurer.setKafkaProperties(this.properties);
    return configurer;
}

使用您的自定义实现。并在其configure()方法中调用适当的listenerContainerFactory.getContainerProperties().setConsumerTaskExecutor()。